Poly(arylene ether)s capped with polymerizable carbon—carbon double bonds are useful components of thermoset compositions, contributing desirable combinations of stiffness, toughness, and heat resistance. Methods of preparing acrylate- or methacrylate-capped poly(arylene ether)s, as well as curable compositions containing them, have been described, for example in U.S. Pat. No. 6,627,704 B2 to Yeager et al. However, these materials are typically prepared by the reaction of a poly(arylene ether) with acrylic or methacrylic anhydride, and these anhydride reagents are relatively expensive, highly reactive, and generate an equivalent of (meth)acrylic acid that must be removed from the product. There is therefore a need for alternative reactive-capped poly(arylene ether)s that are more economical and convenient to prepare.